Nova Patents
US8948210B2

Method, a computer program product, and a carrier for indicating one-way latency in a data network

Summary by NHIP

Network latency measurement method

The method determines one-way latency between unsynchronized nodes by pre-synchronizing clocks, measuring message times, and post-synchronizing to obtain clock difference values. It adjusts sending times using a calculated ratebias derived from the difference between the second and first clock difference values before generating a latency profile.

Claim Score by NHIP

Read claim 1, the broadest

Abstract

Disclosed herein is a method, a computer program product, and a carrier for indicating one-way latency in a data network (N) between a first node (A) and a second node (B), wherein the data network (N) lacks continuous clock synchronization, comprising: a pre-synchronisation step, a measuring step, a post-synchronisation step, an interpolation step, and generating a latency profile. The present invention also relates to a computer program product incorporating the method, a carrier comprising the computer program product, and a method for indicating server functionality based on the first aspect.

US8948210B2, drawing sheet 1
Sheet 1 of 6

Term

Term ended

Expired 9 September 2025, 1 year ago.

  1. Priority
  2. Filed
  3. Granted
  4. Expired
  5. Today

8 claims: 2 independent, 6 dependent

  1. 1
    Broadest claimClaim Score 28, narrow(NHIP)A method for determining one-way latency between a first computer node (A) having a first clock and a second computer node (B) having a second clock, comprising:pre-synchronizing said first clock of said first computer node (A) with said second clock of said second computer node (B), said pre-synchronizing further comprising obtaining a first clock difference value and a first absolute clock value;measuring a sending time and a receiving time associated with each measurement message within a plurality of measurement messages;post-synchronizing said first clock of said first computer node (A) with said second clock of said second computer node (B), said post-synchronizing further comprising obtaining a second clock difference value and a second absolute clock value;interpolating, comprising adjusting the sending time associated with each measurement message, said adjusting based on the sending time, the said first and second clock difference values, and the said first and second absolute clock values, further wherein said adjusting comprises calculating a ratebias, said calculating of ratebias comprising calculating a numberator=(CDIFF 1 −CDIFF 0 ) wherein CDIFF 1 is the second clock difference value, and CDIFF 0 is the first clock difference value, calculating the one-way latency associated with a measurement message in the data network between said first computer node (A) and said second computer node (B) as the difference between the receiving time associated with the measurement message, and the adjusted sending time associated with the measurement message;and generating a latency profile.
  2. 5
    A method for generating a one-way latency profile between a first computer node (A) having a first clock and a different second computer node (B) having a second clock, located in a data network without continuous clock synchronization, comprising:pre-synchronizing said first clock of said first computer node (A) with said second clock of said second computer node (B) to generate pre-synchronization values representing one or more absolute clock values and one or more clock difference values, and obtain a first absolute clock value and a first clock difference value from said one or more absolute clock values and one or more clock difference values, said pre-synchronizing carried out using a plurality of synchronization request and synchronization response messages;following said pre-synchronizing, collecting a predetermined number of time measurements, using a plurality of measurement messages;following said collecting, post-synchronizing said first clock of said first computer node (A) with said second clock of said second computer node (B) to generate post-synchronization values representing one or more absolute clock values and one or more clock difference values, and obtain a second absolute clock value and a second clock difference value from said one or more absolute clock values and one or more clock difference values, said post-synchronizing carried out using a plurality of synchronization request and synchronization response messages;interpolating said plurality of time measurements to create a predetermined number of latency measurements, said interpolating comprising adjusting said time measurements using said first and second absolute clock values and said first and second clock difference values, wherein said adjusting comprises calculating a ratebias;and said calculating of ratebias comprising calculating a numberator=(CDIFF 1 −CDIFF 0 ) wherein CDIFF 1 is the second clock difference value, and CDIFF 0 is the first clock difference value, generating said one-way latency profile based on said latency measurements.
Independent claims2